On Mon, Nov 14, 2011 at 3:48 PM, H.J. Lu <hjl.to...@gmail.com> wrote: > On Mon, Nov 14, 2011 at 9:03 AM, Jan Hubicka <hubi...@ucw.cz> wrote: >> Hi, >> this is hopefully final variant of patch. The epilogue code was broken in >> some >> scenarios for memset, but should work safely now. I also fixed the tables >> for >> core/buldozer/amdfam10 chips. >> >> But before it can be comitted, we need to reoslve copyright assignment >> issues. >> You don't seem to be liested as having copyright assignment, does you company >> have one? Otherwise, please try to get one soon. >> >> Honza >> >> 2011-11-14 Zolotukhin Michael <michael.v.zolotuk...@gmail.com> >> Jan Hubicka <j...@suse.cz> >> >> * gcc.target/i386/sw-1.c: Force rep;movsb. >> >> * config/i386/i386.h (processor_costs): Add second dimension to >> stringop_algs array. >> * config/i386/i386.c (cost models): Initialize second dimension of >> stringop_algs arrays. >> (core_cost): New costs based on generic64 costs with updated stringop >> values. >> (promote_duplicated_reg): Add support for vector modes, add >> declaration. >> (promote_duplicated_reg_to_size): Likewise. >> (processor_target): Set core costs for core variants. >> (expand_set_or_movmem_via_loop_with_iter): New function. >> (expand_set_or_movmem_via_loop): Enable reuse of the same iters in >> different loops, produced by this function. >> (emit_strset): New function. >> (expand_movmem_epilogue): Add epilogue generation for bigger sizes, >> use SSE-moves where possible. >> (expand_setmem_epilogue): Likewise. >> (expand_movmem_prologue): Likewise for prologue. >> (expand_setmem_prologue): Likewise. >> (expand_constant_movmem_prologue): Likewise. >> (expand_constant_setmem_prologue): Likewise. >> (decide_alg): Add new argument align_unknown. Fix algorithm of >> strategy selection if TARGET_INLINE_ALL_STRINGOPS is set; Skip >> sse_loop >> (decide_alignment): Update desired alignment according to chosen move >> mode. >> (ix86_expand_movmem): Change unrolled_loop strategy to use SSE-moves. >> (ix86_expand_setmem): Likewise. >> (ix86_slow_unaligned_access): Implementation of new hook >> slow_unaligned_access. >> * config/i386/i386.md (strset): Enable half-SSE moves. >> * config/i386/sse.md (vec_dupv4si): Add expand for vec_dupv4si. >> (vec_dupv2di): Add expand for vec_dupv2di. > > This may have caused: > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51134 >
The current x86 memset/memcpy expansion is broken. It miscompiles many programs, including GCC itself. Should it be reverted for now? -- H.J.
